Abstract
Changes in platelet function under an anesthesia during surgical operation are not yet clarified. In this paper, the effect of anesthesia with nitrous oxide on platelet functions was examined, and the following results were obtained: 1. ADP induced platelet aggregation did not show any significant change before and after a premeditation with opistan in 20 patients. 2. Blood was collected from 15 patients before and 30 and 90min after a begining of anesthesia under an administration of nitrous oxide for gynecological operation and postoperatively. Platelet count did not show any significant change. Bleeding time was prolonged slightly at 90min after the beginning of anesthesia, with a statistical significance. But no case showed a change beyond the normal range of bleeding time. ADP induced platelet aggregation and platelet factor 3 activity showed no significant change during the observation period. 3. A direct effect of nitrous oxide on platelets was examined in vitro. Nitrous oxide was pumped through the 18G teflon tube into a 10ml siliconized glass tube containing 2ml of the PRP or 3ml of washed platelets for 5 minutes or 30 minutes. The platelet aggregations induced by ADP or collagen were compared with the control, but there were no significant difference in the rates of aggregations. We measured the levels of malondialdehyde (MDA) and c-AMP in washed platelets after incubation for 5 minutes and the level of MDA did not change.
In conclusion, this study revealed that there is no significant inhibition on platelet function under anesthesia with nitrous oxide and operation.
